textproduct: Rapid City

KEY MESSAGES

- Cooler this weekend

- The next organized storm system is expected this weekend, with the best chance of showers and storms Sunday night

- Seasonal temperatures next week with mostly dry weather

UPDATE

Issued at 927 PM MDT Fri Sep 11 2026

Cold front has cleared the FA. Have added some low pops through tonight across most of western SD as an upper jet streak's associated entrance region traverses the area, possibly supporting isold showers/sprinkles. Slightly better chances for precip across far NW SD where weak FGEN forcing will also be in place through Sat morning. Dry Sat with cooler temps, still expecting highs in the 70s most areas, except for NW SD and the Black Hills where 60s are expected. Breezy Sunday with moist easterly upslope flow. This will hold temps down on the SD Plains where 60s and 70s are expected. Main upper trough and associated theta-e ridge will traverse the area Sunday night, supporting an area of showers and storms, starting sct-isold out west then filling in as the system progresses NE across western and central SD. This is where the best chances for precip will be. Isold stronger storms will be possible early on across SW SD if enough low level moisture can advect into the FA ahead of the expected impulse. Seasonal temps and dry most of next week with highs mainly in the 70s, with 80s returning later in the week.

DISCUSSION

(This Afternoon Through Thursday) Issued at 133 PM MDT Fri Sep 11 2026

Cooler weather is settling into the region today. It's being driven into the area by strong northerly to northwesterly winds. Highest reported wind gusts (as of 1PM) have been upwards of 40 to 50 mph. For tonight, winds will slowly diminish through this evening but speeds will really decrease mainly after 9PM. Isolated rain and thundershowers are possible in the area that stretches from NE WY to NW SD later this afternoon through tonight. Severe weather is not expected and rain amounts won't add up to much.

Looking ahead to the weekend, temperatures will be at or below normal for this time of year with highs reaching the upper 60s to 70s. Winds will slowly swing back to the east and southeast on Saturday with wind speeds really increasing Sunday, afternoon gusts will be upwards of 30 to 45 mph, strongest speeds in the SD plains.

Isolated rain and thundershower chances return to the SD plains Saturday into Saturday night but amounts will be on the lighter side, mainly less than a quarter inch if anything. But Sunday into Monday, a passing upper level trough north of the CWA will track eastward. At the surface, low pressure will develop Sunday afternoon and likely travel northeast. As it does, thunderstorms are likely to track through the area late Sunday into Sunday night. Some of those storms could be strong to severe. The SPC and machine learning severe weather models are highlighting a marginal risk of severe weather. Rainfall amounts Sunday into early Monday will be mainly less than a half inch with locally higher amounts possible.

Next week is looking dry with low-end chances for precip late in the week with highs near or below normal for this time of year.

AVIATION

(For the 12Z TAFS Through 12Z Sunday Morning) Issued At 517 AM MDT Sat Sep 12 2026

VFR conditions are expected through the TAF period.

FIRE WEATHER

Issued At 133 PM MDT Fri Sep 11 2026

A RED FLAG WARNING is in effect for SW SD and parts of NE WY until 7 PM MDT this evening. This is for strong, gusty northerly winds and relative humidity down to 12 to 18 percent.

Looking ahead through the weekend, cooler weather is expected with afternoon temps in the 60s to 70s. RH values will bottom out around 30 to 50 percent. Wind gusts will be strong again tomorrow (Saturday) for areas south and southwest of the Black Hills. Sunday will see more widespread gusty winds in the WY and SD plains. Similar weather expected next week.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.